Load lifting machines are used to lift, carry and shift payloads. Typically load lifting machines can take the form of front-end loaders, back-end loaders, excavators, dust bin loaders and the like. The payload is typically crushed stone, sand, debris, rubbish or other solid objects that need to be lifted and moved.
It is often desirable to determine the weight of a payload being lifted in a load lifting machine. For example, the weight being transported by a dump truck needs to determine to ensure the truck meets weight restrictions. One way of doing this is by calculating the weight of the individual payloads being loaded into a dump-truck as the load lifting machine fills the truck.
Apparatus exist for determining the weight of a payload being lifted by a load lifting machine. Such apparatus typically look at the pressure of hydraulic fluid in hydraulic actuators as the payload is being lifted by operating the load lifting machine rig. The difficulty with such apparatus is that they are prone to inaccuracy. This is because the base their calculations on assumptions regarding the characteristics of the load lifting machine rig. Often characteristics such as friction are not taken into account.
It is desirable to provide improved accuracy when calculating weight of payloads being lifted by load lifting machines.